<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <html> <head> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; = charset=iso-8859-1"> <meta name=Generator content="Microsoft Word 10 (filtered)"> <style>  </style> </head> <body bgcolor=white lang=EN-US link=blue vlink=purple> <div class=Section1> Chris,   My string heights are in the 7 = 1/2” range for the most part (a little higher in the middle) and the hammerflange = centers are at 5 ž” so the real problem is getting the 1 ž” = blow distance without peeling the bumper felt off to within 1/8” of the wood. = I’ve dealt with a couple of actions where I would like to raise the rear of = the stack up to avoid the “dreaded repetition lock-up” but have = glued extra felt on the bumpers for the sake of expediency. Do they ever = actually induce warping in the stack at the factory to match the curvature of = the string heights? I’ve never had a stack that rocked on a flat bench or = noticed one that was flexed into a curve on the keyframe.   Eric   <div> Eric Wolfley, RPT Supervising Piano Technician College-Conservatory of Music University of Cincinnati </div>   -----Original = Message----- From: Chris Solliday [mailto:solliday@ptd.net] Sent: Wednesday, July = 20, 2005 12:52 PM To: College and = University Technicians Subject: Re: [CAUT] = Steinway stack height   <div> Eric, the real = relationship in this is of course from the string to the center heights. If  7 = 1/2" is the string height,  correspondingly the hammer center height should be = 5 3/4" which is a difference of 1 3/4" ( a familiar number), so consequently shouldn't the hammer center height be 5 1/2" if the = string height is 7 1/4" ? Is this what Mike Mohr means by "the = action height is unique..." and "Maintaining the relationship between... ?" Just a slight caution regarding lowering = the stack height only in the back, it can result in the dreaded = "repetition lock-up." But with your shanks so close to the cushions it's = probably not a problem. I think Pianotek sells different size rest felts so you can = maintain a good relationship to the shank. As for the straightedge thing it = doesn't mean that you should just stand there forever checking it continuously, = however great a relief from our regular duites this may be, but rather just when = setting the two center mounting blocks and maintaining a slight curve (or = not) to match the string heights. Although it certainly would be a good way to = measure warping if you knew where it had originally been set. Accurate = string height measurements are really key, especially with = Steinways, for this kind of work.  Chris </div> <blockquote style='border:none;border-left:solid black = 1.5pt;padding:0in 0in 0in 3.0pt; margin-left:3.0pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'= > <div> ----- Original Message = ----- </div> <div style='font-color:black'> From:</spa= n> <a href="mailto:WOLFLEEL@UCMAIL.UC.EDU" = title="WOLFLEEL@UCMAIL.UC.EDU">Wolfley, Eric (wolfleel)</a> </div> <div> To:= <a href="mailto:caut@ptg.org" title="caut@ptg.org">'College and = University Technicians'</a> </div> <div> Sent:</spa= n> Thursday, July 21, 2005 11:29 AM </div> <div> Subject:</= span> RE: [CAUT] Steinway stack height </div> <div>   </div> Thanks Chris = and all that replied. I’ll thumbtack the specs to the wall so I won’t = misplace them. I did contact Kent Webb and the current spread specification is 4 13/32” which translates to 4.40625”   The piano in = question is indeed of 1968 vintage (Mr. Purdy) and was originally Teflon with the = big fiber knuckles. I isolated the problem to two sources: The rear of the stack = was 1/16” too high (3 5/16”)…easy enough, I carefully = planed the shoes down. The shank bumpers on the new wippens I want to use (Tokiwa = miracle wipps) are 1/8” higher than the original. We save a lot of old = parts here…it was good to have some samples to check. This piano had a = new soundboard installed a few years ago (before I started here) and = obviously the string heights are lower now than its original incarnation. =   In = Chris’s post below I can’t exactly visualize what they are talking about when = they say “continually check for straightness with the straightedge on top = of the hammershank flanges”. My only guess is that if the mounting = blocks aren’t all on the same plane the hammer rail could warp down or up where a = stack bracket is screwed down but it seems like it would have to be really = bad for this to happen.       <div> Eric Wolfley, RPT Supervising Piano = Technician College-Conservatory of = Music University of = Cincinnati </div>   -----Original = Message----- From: Chris Solliday [mailto:solliday@ptd.net] Sent: Monday, July 18, = 2005 5:07 PM To: College and = University Technicians Subject: Re: [CAUT] = Steinway stack height   <div> "B" at note 62 = in NYC hammer flange 5 3/4" </div> <div> rep flange 3 = 1/4"  based on string height of 7 1/2"    you didn't say if pre = 84 or post or the new incarnation but the spread pre 84 was  4.381" = and post 84 was 4.395"  This may have changed on the latest and = greatest and for that I suggest you call Kent Webb or email him.  I = think it is important to note that according to Mike Mohr's Forefinishing Notes, = which I consider a reliable source, "Set Action Frame Height" says "IMPORTANT NOTE: the action stack height, as = determined by the thickness of the mounting blocks. This action height is = unique for each instrument, and is the result of the individual string height for = a piano. String height variables are the result of the plate fitting and = belly operations... String heights change from bass to treble usually in an = arched or crowned manner. These numbers for note # 62 represent an average. = Maintaining the relationship between the stack height and the string height = ensures: A) the proper BLOW distance at the same time the hammershank is properly off = the cushion. and B) the proper HAMMER ROTATION is needed to minimize = overstriking or shallow striking conditon. NOTE; if string height is lower or higher = than above, keep the relationship the same..." (and later after = shimming or planing the bass and treble mounting blocks) "continually check = for straightness with the straightedge on top of the hammershank = flanges." I know you only asked for numbers, but what the heck, I felt like = sharing. BTW I'm sure you remember that we discovered when shimming or planning it = is best to rotate the stack on the hammer flange pin axis which means adjusting = the front foot differently than the back foot. Of course there are even = greater subtleties to this process but then you did just ask for the = numbers. Stay well, Chris Solliday   </div> <blockquote style='border:none;border-left:solid black = 1.5pt;padding:0in 0in 0in 3.0pt; margin-left:3.0pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'= > <div> ----- Original Message = ----- </div> <div style='font-color:black'> From: <a href="mailto:WOLFLEEL@UCMAIL.UC.EDU" title="WOLFLEEL@UCMAIL.UC.EDU">Wolfley, Eric (wolfleel)</a> = </div> <div> To:= <a href="mailto:'caut@ptg.org'" = title="caut@ptg.org">'caut@ptg.org'</a> </div> <div> Sent:</spa= n> Tuesday, July 19, 2005 9:53 AM </div> <div> Subject:</= span> [CAUT] Steinway stack height </div> <div>   </div> Hi All,   I’m sure somebody = out there knows the specs for the distance from the keybed to hammerflange center = and keybed to wippen center for a Steinway B. I have these written down = somewhere but can’t find them and I don’t trust my memory. I’m correcting a problematic action and believe the stack to be too high = since to get the proper blow distance the shank cushions have been reduced to = nubs. The bore distance of the hammers is correct and the string heights are in = the normal range.   Thanks!   Eric Wolfley, RPT Supervising Piano = Technician College-Conservatory of = Music University of = Cincinnati   </blockquote> </blockquote> </div> </body> </html>